Support for a new workstation cluster is requested to meet the computing needs of nine NIH-funded faculty and their research groups in the Department of Chemistry at UCI. The cluster consists of a multi- processor server and six Silicon Graphics O2 R1200 workstations with molecular modeling software. NIH-supported research projects for which the requested computing resources is needed are: 1) Structural modeling of biopolymers and model systems: Modeling the structure and dynamics of polysaccharides; design of new phosphatase inhibitors through active-site modeling and library searching; predicting and understanding the structure of artificial beta-sheets; modeling structure and dynamics of pulmonary surfactant proteins. The last is a new hire who does not yet have NIH support. 2) Prediction of organic reactivity and selectivity: Design of a variety of new stereoselective reactions; synthesis of complex natural products and other targets of biological and pharmaceutical interest. The number and breadth of the NIH-supported research projects described herein are large. While most of the researchers are primarily experimentalists, significant computational work is a key component of all of these projects. Researchers rely on a centralized facility for most effective utilization of CPU and graphics resources among a large number of researchers who are primarily experimentalists and thus intermittent users, and for cost savings. A significant multi-processor computer will allow larger scale calculations currently inaccessible to us. The strong Chemistry theory group at UCI, a Molecular Modeling Facility Manger who is a Ph.D. chemist with computational chemistry expertise, and a commitment to training graduate researchers in modeling methods who have made our existing shared computing resources extremely valuable. Existing hardware is becoming obsolete and new hardware has become an urgent need. UCI has made a significant long-term funding commitment to excellence in computational chemistry research and instructions through the salary of the Facility Manager.